Fix bypass_url and errors with no headers

When using bypass_url the endpoint_override needs to be set in the
SessionClient.
Don't assume all responses have a Content-Type

Fixes Bug: 1532278
Change-Id: I5e1319aae28e16448e20dd2b41836341f3156c59

magnumclient/common/httpclient.py

@@ -295,6 +295,7 @@ class SessionClient(adapter.LegacyJsonAdapter):
 
         kwargs.setdefault('user_agent', self.user_agent)
         kwargs.setdefault('auth', self.auth)
+        kwargs.setdefault('endpoint_override', self.endpoint_override)
 
         endpoint_filter = kwargs.setdefault('endpoint_filter', {})
         endpoint_filter.setdefault('interface', self.interface)

magnumclient/exceptions.py

@@ -61,7 +61,7 @@ def from_response(response, message=None, traceback=None, method=None,
         # NOTE(hongbin): This allows SessionClient to handle faultstring.
         response.json = lambda: {'error': error_body}
 
-    if (response.headers['Content-Type'].startswith('text/') and
+    if (response.headers.get('Content-Type', '').startswith('text/') and
             not hasattr(response, 'text')):
         # NOTE(clif_h): There seems to be a case in the
         # openstack.common.apiclient.exceptions module where if the

magnumclient/tests/test_httpclient.py

@@ -15,10 +15,12 @@
 
 import json
 
+import mock
 import six
 
 from magnumclient.common import httpclient as http
 from magnumclient import exceptions as exc
+from magnumclient.openstack.common.apiclient.exceptions import GatewayTimeout
 from magnumclient.tests import utils
 
 
@@ -269,3 +271,29 @@ class SessionClientTest(utils.BaseTestCase):
                                   'GET', '/v1/resources')
 
         self.assertEqual('Internal Server Error (HTTP 500)', str(error))
+
+    def test_bypass_url(self):
+        fake_response = utils.FakeSessionResponse(
+            {}, content="", status_code=201)
+        fake_session = mock.MagicMock()
+        fake_session.request.side_effect = [fake_response]
+
+        client = http.SessionClient(
+            session=fake_session, endpoint_override='http://magnum')
+
+        client.json_request('GET', '/v1/bays')
+        self.assertEqual(
+            fake_session.request.call_args[1]['endpoint_override'],
+            'http://magnum'
+        )
+
+    def test_exception(self):
+        fake_response = utils.FakeSessionResponse(
+            {}, content="", status_code=504)
+        fake_session = mock.MagicMock()
+        fake_session.request.side_effect = [fake_response]
+        client = http.SessionClient(
+            session=fake_session, endpoint_override='http://magnum')
+        self.assertRaises(GatewayTimeout,
+                          client.json_request,
+                          'GET', '/v1/resources')